Research On Signal Conditioning Circuits Of High-speed Data Acquisition System

Data acquisition technology is a branch of Information Science, which studies data collection, storage, treatment and control work. A data acquisition system is often made from four major components: a data acquisition, signal conditioning, data conversion and storage. High-Precision measuring accuracy can be acquired through high-performance signal conditioning circuit. Reasonable front-end processing structure of data acquisition system can simplify circuit design, reducing the difficulty of implementation, and ensure reliable operation of the system.This article takes signal conditioning part of high-speed data acquisition system as the research object. Signal conditioning can achieve the large range of input signal required for measurement range of ADC, it can provide a favorable dynamic range to input signal for data acquisition system, so a reasonable signal conditioning program has very important significance for high-speed data acquisition system.In this paper, implementation method for signal conditioning part in high-speed data acquisition is studied, impedance matching and transformation technique, signal attenuation and amplification method, analog-digital conversion technique are applied. Compared and demonstration some scheme and relative technologies of front-end signal conditioning in high-speed data acquisition system and some concrete implementation methods for functional circuit were given. Impedance matching and transformation, attenuation, amplification, high-speed ADC and implementation of peripheral circuit are discussed in this paper; besides a specific circuit design and description of the key devices are given. Finally choose the optimal implementation scheme of each functional circuit and design a signal conditioning circuits with two-synchronous-channel for high- speed data acquisition, each channel's real-time sampling rate is 1GSPS, 8-bit vertical resolution, input bandwidth is 200MHz.The paper's research content has valuable practical significance for High-speed data acquisition front-end signal conditioning products,such as digital oscilloscope, spectrum analyzer, and so on.